This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Biological minerals such as vertebrate bone and tooth exhibit remarkable levels of hierarchy that are controlled over multiple length scales to produce superior mechanical properties compared to their individual building blocks. The process of mineralization involves the deposition of a protein scaffold upon which controlled crystallization of carbonated apatite occurs. In an effort to create biomimetic materials for use with mineralized tissues our lab is exploring the use of peptide amphiphiles as a synthetic scaffold. These molecules have been utilized by the Stupp laboratory to achieve a collection of bioengineering goals: as cell and tissue artificial scaffolds;as biomaterials that direct stem cell differentiation cell migration cellular response and tissue regeneration after injury;as vehicles for drug cell peptide and protein delivery [8-12];and as materials that induce biomineralization for bone and tooth enamel formation [13-15]. The proposed experiments focus on understanding the supramolecular structures that these PA molecules create. Additionally we plan to utilize PA scaffolds as a structural matrix for supporting nucleation and growth of biologically relevant mineral and characterize the inorganic-organic relationships at the nanoscale using X-ray diffraction. Understanding the assembly of peptide amphiphiles and interactions occurring at the organic-inorganic interface in biomineralized structures can elucidate structure-function relationships achieved by biology and enable the development of novel intelligent materials.